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प्रश्न
Comment on the role of placenta as an endocrine gland.
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उत्तर
Placenta acts as an endocrine gland and produces the human chorionic gonadotropins, human placental lactogen, oestrogen, progesterone and relaxin (later stages of pregnancy). These hormones support foetal growth and help in the maintenance of pregnancy. Hormones like oestrogen, progestogen, cortisol and prolactin are increased several folds in the maternal blood.
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संबंधित प्रश्न
When and where do chorionic villi appear in humans?
Explain Rh factor incompatibility during pregnancy.
Which of the following hormones is not secreted by human placenta?
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The concentration of which of the following substances will decrease in the maternal blood as it flows from embryo to placenta through the umbilical cord?
The human foetus within the uterus
- Oxygen
- Amino Acids
- Carbon dioxide
- Urea
Placenta is
Except endocrine function, what are the other functions of placenta.
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Reason: Cells in the embryonic stage are mortal, differentiated and easy to manipulate.
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| Column I | Column II | ||
| I. | 8 weeks | (P) | Limbs and external genital organs |
| II. | 12 weeks | (Q) | Limbs and digits develop. |
| III. | 20 weeks | (R) | Body hair develops. |
| IV. | 24 weeks | (S) | Eyelids separate. |
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